Lots of info out here, but here's a good thread that might help you: http://eab.abime.net/showthread.php?t=32256
This line revealed where I could get darn scsi.device file for A4000!!! ;
"Open up Dopus and in the left window go to the “MyFiles/LargeHD/128GB Support/SCSI_IDE_43_24/Patched” drawer and in the right window go to the “Devs” drawer."
So thank you thank you so much for helping me out in right direction, now she boots fine with this 16Gb card!
Unbelievable, this file was here on this card all the time, but I couldn't find it before. So indeed it was just what I really needed.
Now got that extra motivation to tune her up. Finally will tinker with my newly bought Indivision card to get some hi-res Worbench pleasure!